If you got a higher score on the SAT at the end of 9th grade than on the PSAT in 11th (drop in reading; uptick in math), would you bother taking the SAT again? My guess is the question of whether you want stress of test prep? GPA is UW B+ range so merit is not really on the table regardless of SAT score. Without merit being likely because on GPA, does it make sense to try to improve the score? Or would you try the ACT and then be done?
I think it’s always a good idea to try both the ACT and SAT. The question for the SAT is are your scores in line with the schools in which you are interested? If so then don’t retake. If not then do so.
I would try a practice ACT as well. Some students do substantially better on one format vs the other.